Dyeing process



Patented Mar. 7, 1933 UNITED STATES PATENT, OFFICE WILLIAM R. MOORHOUSE, OF NEW YORK, N. Y., ASSIGNOR TO NATIONAL ANILINE &;

CHEMICAL COMPANY, INC., OF NEW YORK, N. Y A CORPORATION OF NEW YORK DYEING rnocnss No Drawing.

This invention relates to the dyeing of textile fabrics by means of vat dyes.

There are three principal methods generally employed for dyeing cotton and rayon -piece goods with vat dyes, namely: (1) work- 7 ding the material to be dyed with the unreduced dyestuff, and then working the padded material in a reducing bath, or jigging it.

The dyeing of textile fabrics and fibres with vat dyes by the third method the pad and jig method (also known as the pigment padding method), is disclosed by Schlegel in United States Patents Nos. 893,384: and 1,185,943. According to this process, the material to be dyed with the vat dy'estuff (e. g., cotton fabric, yarn, and the like) is padded or printed with a paste which contains the vat dyestuif in the unreduced form, (pigment form), water and a suitable thickener. The material is then dried and subsequently treated, or it is subsequently treated without being dried. The material so prepared is then treated on the jigger with a solution or suspension of an alkaline reducing agent, such as, for example, alkaline hydrosulfite, in order to develop the color on the fibre. The material is then finished inany suitable manner.

The present invention relates to improvements in the process of dyeing cotton and regenerated cellulose (rayon) piece goods and yarn by the said pad and jig method, and is especially concerned with improvements in the padding process and the padding liquor.

One of the objects of the present invention is the provision of a padding liquor which produces dyeings of improved strength and brightness of shade.

Another object of the invention is the in-. corporation into a padding liquor of a substance which increases the rapidity with which the vat dyestufi' contained in the liquor is developed on the fibre in the jig.

Another object of the invention is the incorporation into a padding paste or liquor of Application filed July 21, 1928. Serial No. 294,586.

a substance which enhances the smoothness of the paste and permitsit to be more read- 1ly strained.

According to the present invention, the material to be dyed with a vat dyestufi is padded with a padding liquor which con tains the vat dyestufl' in the unreduced form' and a soluble sulfide. The expressionwat dyestufi' in the unreduced form, as used in this description and in the claims, denotes the vat dyestuif as distinguished from its leucoderivatives.

It has been found, according to the present invention, that the presence in the padding liquor of a suitable sulfide (for example, an alkali-metal sulfide) improves the dyeings obtained by the process, as indicated by increased strength and brightness of shade, as compared with dyeings obtained under identical conditions but with the omission of the sulfide.

It has furthermore been found, according to the present invention, that if into the padding liquor containing the vat dyestufi there is incorporated a suitable sulfide, the working qualities of the padding liquor or paste are improved,.as evidenced by a smoother paste which can be strained more readily.

In addition, when material padded with a padding liquor containing a suitable sulfide is subjected to the action of the reducing bath on the jig. the color is developed on the fibre with greater rapidity than when the sulfide is absent.

In carrying out the process according to a preferred embodiment of the present invention, a padding liquor is.prepared containing a mixture of a suitable vat dyestufi' in the unreduced form, a soluble alkali-metal sulfide (such as, sodium monosulfide), water, and a suitable gum or thickener (such as, gum arabic, gum tragacanth, glue, etc.) The mixture is strained through a fine meshed cloth, and the material to be dyed (such as, cotton, linen, or rayon piece goods or yarn) is padded or printed with the resulting liquor. The

- padded or printed cloth is then treated in the bath), and subsequently finished in the customary way.

In preparing the padding liquor, the vat dyestufi', e. g. an anthraquinone vat dyestufl' or an indigoid vat dyestufi', is preferably employed. in the paste form. Among the anthraquinone vat dyestufi's which are particularly useful in connection with the invention are the anthraquinone azine vat dyestufi's; e. g., indanthrones, fiavanthrones, etc.

Among the sulfides suitable for incorporation into the padding liquor, there may be mentioned, by way of example, the soluble sulfides, e. g., hydrogen sulfide and its alkalimetal salts (sodium sulfide, potassium sulfide, ammonium sulfide, etc.).

The invention will be described in connection with the following examples which are iven for illustrative purposes only, it not fieing intended to limit the procedure to the details given, since the process can be varied throughout wide limits without departing from the spirit or scope of the invention.

Example 1.-Cotton piece goods is padded in a padding liquor containing the following ingredients in the following approximate amounts Water sufiicient to make up volume to approximately 1700 cc.

The liquor can be priefpared, for example, by mixing the dyestu in the unreduced form with the sodium sulfide, in the form of a solution in water, adding the gum arabic and gum tragacanth in the form, of a water solution, and bringing the total volume up to the desired volume by addition of water. The mixture is then strained through a cloth of fine mesh.

The padded cloth is treated on the jig in an alkaline hydrosulfite bath, wherein the color rapidly develops, and is then finished as usual. Dyeings are obtained of increased brightness and fullness ofshade as compared with those obtained by the employment of a padding liquor containing no sulfide.

EwampZe'2.Cotton cloth or yarn is padded in a padding liquor similar to the one described in Example 1, the padding liquor containing, however, 30 s. of Carbanthrene yellow G double paste (Color Index No. 1118) and 8.1 gms. of sodium monosulfide (fused) instead of the dyestufi and quantity of sodium sulfide therein given, the other ingredients being the same. The cloth or yarn is subsequently treated as in Example 1.

Example 3.-The procedure and ingredients are the same as in Example 1, except remove that the padding liquor contains 60 gms. of Jade green paste (Color Index No. 1101) and 7.5 gms. of sodium monosulfide (fused) instead of the dyestufi and quantity of sodium sulfide therein set out.

'wample 4.The procedure and ingredients are the same as in Example 1, except that 20 gms. of Hydron brown 0 G powder (Color Index No. 1168) and 8 gms. of sodium sulfide (fused) are used instead of the dyestufii' and quantity of sodium sulfide of said example.

Example 5.Cotton piece goods is padded in a padding liquor containing 20 gms. of Ciba blue 2B powder (Color Index No. 1184). and 2.5 gms. of sodium sulfide (fused), together with the gums and water in the proportions of Example 1. The padded goods is subsequently finished as above described.

As pointed out above, the invention is not limited to the above examples, but broadly contemplates the incorporation of a soluble sulfide into a padding liquor containing a vat dyestufi in the unreduced form. The vat dyestuffs which are useful in the process are not limited to those given in the above examples, but other suitable vat dyestuffs may be employed, such as other vat dyes of the anthraquinone series (including the indanthrones, flavanthrones, benzanthrones, etc.) and of'the indigoid series.

The quantities of. dyestufl' to be used will obviously vary with the particular dyestufi' employed and with the shade and strength of color desired.

The quantities of sulfide incorporated into the liquor will also vary within considerable limits depending u on the individual dyestufi' treated and t e amount of dyest-ufi used. Thus, for exam le, in padding with Carbanthrene yellow double paste, satisfactory results are obtained with from about 3 to about 50 per cent by weight of anhydrous sodium sulfide based on the weight of double paste employed. It is to be noted, however, that too large a quantity of sulfide is to be avoided, since it has been found that in such cases instead of an improvement being obtained in the dyeings, no improvement and even deleterious results are obtained. Furthermore, the addition of too much sulfide causes the paste to lump, and the material does not pad evenly. Instead of the sodium sulfide used in the above examples, other soluble sulfides may be used, such as, hydrogen sulfide, potassium sulfide, and ammonium sulfide; and the crystallized sulfide may be employed as well as the anhydrous material, providing proper allowance is made for its water content.

Various thickeners may also be used, either alone or in admixture, instead of the gums described in the above examples (for example, glue, gelatine, and other mucilaginous materials), and the quantity to be 'employed may also vary, as will be evident.

The padding liquor is preferably prepared in the mannerabove described, but it will be evident that it also may be prepared in a variety of ways, and that the order of mixing the ingredients may be suitably varied.

The process as described is an economical and rapid one. Brighter and fuller shades are obtained than by the prior pad and jig processes, and the development of the color on the jig is more rapid.

As many apparently widely difierent embodiments of this invention may be madewithout departing from the spirit thereof, the 'invention is not intended to be limited to the above specific description, except as indicated in the appended claims.

Having thus described my invention what I claim and desire to secure by Letters Patent is:

1. In the process of dyeing with a vat dyestufi. by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the vat dyestuff substantially entirely in the unreduced form and a soluble sulfide.

2. In the process of dyeing with a vat dyestuff by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the vat dyestufl substantially entirely in the unreduced form and an alkalimetal sulfide.

3. In the process of dyeing with a vat dyestuff by the pad and jig method, the 'improvement which comprises padding the material to be dyed with a padding liquor which contains the dyestufi in the unreduced form and hydrogen sulfide.

4. In the process of dyeing with a vat dyestuff by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the vat dyestufi substantially entirely in the unreduced form and sodium sulfide.

5. In the process of dyeing with a vat dyestuff of the anthraquinone series by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the vat dyestutf of the anthraquinone series in the unreduced form and a soluble sulfide.

6. In the process of dyeing with a vat dyestufi of the anthraquinone series by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the vat dyestuif of the anthraquinone series in the unreduced form and hydrogen sulfide.

7. In the process of dyeing with a vat dyestuif of the anthraquinone series by the pad and jig method, the improvement which com reduced form and 'an alkali-metal sulfide.

8. In the process of dyeing with an anthraquinone azine vat dyestufi' by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor'which contains the anthraquinone azine vat dyestufi in the unreduced form and an alkali-metal sulfide.

9. In the process of dyeing with an anthraquinone azine vat dyestufl' by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the anthraquinone azine vat dyestufi in the unreduced form and sodium sulfide.

10. In the process ofdyeing with an indanthrone by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the indanthrone in the unreduced form and a soluble sulfide.

11. In the process of dyeing with an indanthrone by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the indanthrone in the unreduced form and sodium sulfide.

12. In the process of dyeing with dichlorindanthrone by the pad and j1g method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the indanthrone in the unreduced form and sodium sulfide.

13. In the process of dyeing with a vat dyestufl' of the indigoid series by the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the vat dyestufi of the indigoid series substantially completely in the unreduced form and a soluble sulfide.

14. In the process of dyein with a vat dyestuff of the indigoid series y the pad and jig method, the improvement which comprises padding the material to be dyed with a padding liquor which contains the vat dyestufi' of the indigoid series substantially completely in the unreduced form and sodium sulfide.

15. A padding liquor comprising water, a vat dyestufi in the unreduced form, a soluble sulfide and an adhesive.

16. A padding liquor comprising water, a vat dyestufi in the unreduced form, sodium sulfide and an adhesive.

17. A padding liquor comprising water, a vat dyestufi' of the anthraquinone series in the unreduced form, an alkali-metal sulfide and an adhesive.

18. A padding liquor comprising water, a vat dyestufli' of the anthraquinone series substantially completely in the unreduced form,

sodium sulfide and an adhesive.

19. A padding liquor comprising water, an indanthrone in the unreduced form, an al- 5 kali-metal sulfide and an adhesive.

20. A composition comprising a vat dyestufi substantially completely in the unreduced form and a soluble sulfide.

21. A composition comprising an anthraquinone vat dyestufl' substantially completegi in the unreduced form and a soluble sul- 22. A composition comprisin an anthraquinone vat dyestufl substantia ly completely in the unreduced form and sodium sulfide.

23. A composition comprising an anthraquinone azine vat dyestuif substantially completely in the unreduced form and an alkalimetal sulfide.

24. A composition comprising an indanthrone substantially completely in the unreduced form and an alkali-metal sulfide.

25. A com osition comprising dichlor-indanthrone su stantially completely in the unreduced form and sodium sulfide.

26. A composition comprising Water, a vat dyestuff of the indigoid series substantially completely in the unreduced form, and a soluble sulfide.

27. --A composition comprising water, a vat dyestufi of the indigoid series substantially completely in the unreduced-form, and sodium sulfide.

28. Material padded with the composition of claim 20.

29. Material padded with the composition of claim 22.

30. Material padded with the composition of claim 23.

40 31. Material padded with the composition of claim 24.

32. Material padded with the composition of claim 26.

33. Material padded with the composition of claim 27 In testimony whereof I aflix my signature.

WILLIAM R. MOORHOUSE. 

